Electrical testing apparatus.



H. G. INGRAM.

ELECTRICAL TESTING APPARATUS.

APPLICATION FILED MAR. 21, 1912 1,056,995. Patented Mar. 25, 1913.

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UNITED S'TiitTES PATENT OFFICE.

HORACE G. INGRAM, or JUNIATA, PENNSYLVANIA, AssIGNoB; or ONE-HALF, 'ro

' f SAM EL GOLDBERG, oF'AL'rooNA, PENNSYLVANIA.

ELECTRICAL TESTING APPARATUS.

To all whom it may concern: 7 Be it known that I, HonAon'G. INGRAM, a citizen of the United States,-residmg at Juniata, in the county of Blair and State of Pennsylvania, have invented new and useful Improvements for Electrical Testing Apparatus, of which the following is a specification. 7

The'object of my invention is to provide 10 an apparatus whichis exceedingly sensitive,

compact and convenient for use in places that are not readily accessible, which can, of course, be used in any place but is particularly-intended for places where the operator has-the use of only one hand; With this-and otherpart of the clothin other objects ii -view my invention consists of a combination and arrangement of parts Sl'iOWei'i in the accompanyingdrawing, in .iwhiehi- Figure llisa sectional view of the receiver, and also of theother parts in elevation. Fig. 2 is'a-side view of the receiver showing the i sectional head spring folded and turnedback li ly invention consists of a. casing 1 such as is used for an ordinary telephone re- .ator free. This casing 1 has a cap 3 49 which has a downwardly bent flange 2- 50 the casing 1 by means of a screw ceiver for operators in which a spring passing over the head holds it permanently to the ear, thereby leaving the hands of the opercontaiuing a screw thread. the cap 3 is an opening 1, which perinits the free entrance of the air and there by transmits the vibrations of the din-- phragm 5, which is held over the central support or magnet 6 in the ordinary manner by. being gripped between the screw cap 3 and the outer edge of the casing 1. The magnet hold permanently to 7 7 a and any means ordinarily employed lot that purpose can be used to prevent rotation ot the magnet 6 by reason ot the strain put upon it, as will be shown hereafter. Oi'di nai'ily it is sullicient to merely employ a tric- Sp'ecitication of Letters Patent.

At the center of Patented Mar. 25, 1913.

Application filed March 21, 1912'. Serial m. 685,394.

tional resistance between the inner end of the magnet 6 and the casing 1. At the upper port-ion of the casingl is an L shaped piece 8 of screws. The free end of this piece has rotatably secured to it a sectional spring 9 by means of a rivet 12. Projections and depressions formed on the sliding portion between 9 and 12 may he employed to hold the spring in the proper position when extended, and at diametrically opposite points when closed. The OtliQ1':SQC-

secured thereto by'nieans tioiis of the spring are shown at\- 9 9 9 and l0. Thesc'various sections are secured together by rivets 13 and are held in position in the same way as the first section 9. The lowerend of the port-ion 10 is bent slightly outward, shown at 11, so as to prevent catching'on. the hair of the operator. This sectional spring 9 folds back in these-me manner as a sectional foot rule, such as is in common use. today.

,When folded and turned down it is as shown in Fig. '2. In this position itforms a hook by means of which theoasing can be secured to the belt bymerely sliding then-hook over the upper edge, orit may be secured in :1 pocket or over the upper band of the trousers; v

Pivoted on the magnet 6, is a spool 15 containing insulated iiiagiietwire 16, which may he in one or two coils,

such as is ordinarily en'iployed in a tele phone receive-r. If it is in two coils, a small switch is used to employ either one or both coils, tl'ie eby increasing or decreasing the strength of the receiving apparatus. Over these eoilsotwire is placed a band of material which may be separated from the spool 0( ftt5l't1ll0tl thereto. The objectof this is to cover the wire and leave a smooth surface upon which to wind a double cord l9 and 2O The terminals of the inner coil of magnet wire are brought out to points 19 and 20. These points may have binding screws or any other means of fastening may be used. To these same points are fastened the ends of the double cord ll) and 9.0.- To the spool 15 are secured pawls 17 having projections which are ai'hipted to enter notches 18 in the unigiicl (3 in the same manner as on a shade roller. A spring 14 is secured at our end by a pin 29 to the spo0l 15 and at its other end by a. pin 30 t3 the magnet 6. From this construction it will be readily seen that if the spool is wound up the springd l willexert a torsional pull uponthe same and if the cord f 19 and 20 is fastened by its ends to the terminals 1.9,'and 20* a slight pull. and a sudden release, such as are (an-- ploycd in operating a shade roller, will cause the spring 14 to wind the cord lt and 920 upon the outer portion ofthe spool 15,;thereby bringing the ends- :51 and 23 close to or. againstthe casing 1 v.

When used for testing one terminal, such ;as 21 having'a point 22; is inserted in Vlhe one pole 28 of a pocket battery F 25 and the other pole of the battery is brought out of the casing at a point, such as 27 A spring-hook, such as shown at 26, is

fastened to the casingfor the battery, so

that it can readily be secured on the edge of a garment. From this construction itcan readily be seen that the operator can workin places where he is compelled to use one .hand,'because he :can detachably secure one end of the circuit to be tested to the hook 27 using the terminal 24 to touch the other side of the circuit, which will give him afclick in the ear if sliort-circuited.

If it is open there will be no sound produced and the two POItluflS of the circuit are, therefore, securely insulated from each other. I This arrangement for testingis very compact and complete and can readily be carried by a lineman or ing usefor the same."

' I do not wish to confine myself absolutely I mcchanician. havto the specified'construction shown, but any other suitable means thatrina'y be substituted withoutalteringthe essential ortions of my invention, are conteiiiplate as a part thereof. 1

I am aware that -telephone reccive'rs of the general character shown here are old,

and it is also old to hold such the car by means of a spring. Therefore, what I claim is receivers to 1.- T hecombination. in a receiver of a (5115- ing, a central support; in said casing, a

spool pivoted on said support,i a coil .of magnet wire on said spool, a terminal cordat v tached .to 'said spool and magnet wire, means for holdingsaid spool in any ad] listed position, and means for automaticallyrotating-h said spool upon the release of said holding means for winding the terminal cord -on said spool. a

2.. The combination in a receiver of a casing, a central support in said casing adapt- ALEX -WEIR,

A. .C. RICH. v 

